TY - JOUR
T1 - Microsatellite (SSR) variation in a collection of Malus (apple) species and hybrids
AU - Hokanson, S. C.
AU - Lamboy, W. F.
AU - Szewc-McFadden, A. K.
AU - McFerson, J. R.
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 2001
Y1 - 2001
N2 - A collection of 142 accessions of 23 Malus species, derived hybrids and cultivar accessions from the USDA-ARS Plant Genetic Resources Unit's core collection, which represents an extensive range of Malus species, was screened with a set of previously described SSR (simple sequence repeat) markers. The markers were used to determine genetic identities, estimate genetic diversity, identify genetic relationships among the accessions, and determine the utility of SSR primers developed from Malus x domestica for making genetic assessments across the whole Malus genus. All eight primer pairs amplified multiple fragments when used in polymerase chain reactions with DNA from these accessions. High levels of variation were detected with a mean of 26.4 alleles per locus and a mean direct count heterozygosity across all eight loci equal to 0.623. The eight primer pairs used in this study unambiguously differentiated all but five pairs of accessions in this collection of 142 accessions of 23 Malus species, derived hybrids and cultivars. These SSR data were not useful in identifying genetic relationships among this diverse collection of accessions, with the majority of the accessions not clustering in ways concordant with taxonomic information and/or geographic origin. The resulting phenogram resolved only two meaningful clusters, for the taxonomically isolated Section Chloromeles and for M. fusca accessions, reflecting genetic relationships arising from geographic origin. The detection of identical accessions in the collection, which were previously considered to be unique, highlights the critical need to further bolster collections of certain Malus species.
AB - A collection of 142 accessions of 23 Malus species, derived hybrids and cultivar accessions from the USDA-ARS Plant Genetic Resources Unit's core collection, which represents an extensive range of Malus species, was screened with a set of previously described SSR (simple sequence repeat) markers. The markers were used to determine genetic identities, estimate genetic diversity, identify genetic relationships among the accessions, and determine the utility of SSR primers developed from Malus x domestica for making genetic assessments across the whole Malus genus. All eight primer pairs amplified multiple fragments when used in polymerase chain reactions with DNA from these accessions. High levels of variation were detected with a mean of 26.4 alleles per locus and a mean direct count heterozygosity across all eight loci equal to 0.623. The eight primer pairs used in this study unambiguously differentiated all but five pairs of accessions in this collection of 142 accessions of 23 Malus species, derived hybrids and cultivars. These SSR data were not useful in identifying genetic relationships among this diverse collection of accessions, with the majority of the accessions not clustering in ways concordant with taxonomic information and/or geographic origin. The resulting phenogram resolved only two meaningful clusters, for the taxonomically isolated Section Chloromeles and for M. fusca accessions, reflecting genetic relationships arising from geographic origin. The detection of identical accessions in the collection, which were previously considered to be unique, highlights the critical need to further bolster collections of certain Malus species.
KW - Apple
KW - Genetic relatedness
KW - Germplasm management
KW - Malus species and hybrids
KW - Microsatellite markers
UR - http://www.scopus.com/inward/record.url?scp=0035053344&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0035053344&partnerID=8YFLogxK
U2 - 10.1023/A:1017591202215
DO - 10.1023/A:1017591202215
M3 - Article
AN - SCOPUS:0035053344
SN - 0014-2336
VL - 118
SP - 281
EP - 294
JO - Euphytica
JF - Euphytica
IS - 3
ER -